From owner-freebsd-questions Fri Aug 23 10: 4: 9 2002 Delivered-To: freebsd-questions@freebsd.org Received: from mx1.FreeBSD.org (mx1.FreeBSD.org [216.136.204.125]) by hub.freebsd.org (Postfix) with ESMTP id B3D0E37B400 for ; Fri, 23 Aug 2002 10:04:06 -0700 (PDT) Received: from mailsrv.otenet.gr (mailsrv.otenet.gr [195.170.0.5]) by mx1.FreeBSD.org (Postfix) with ESMTP id 589D743E42 for ; Fri, 23 Aug 2002 10:04:05 -0700 (PDT) (envelope-from keramida@ceid.upatras.gr) Received: from hades.hell.gr (patr530-b240.otenet.gr [212.205.244.248]) by mailsrv.otenet.gr (8.12.4/8.12.4) with ESMTP id g7NH41pD006985; Fri, 23 Aug 2002 20:04:02 +0300 (EEST) Received: from hades.hell.gr (hades [127.0.0.1]) by hades.hell.gr (8.12.5/8.12.5) with ESMTP id g7NH40Dq062265; Fri, 23 Aug 2002 20:04:00 +0300 (EEST) (envelope-from keramida@ceid.upatras.gr) Received: (from charon@localhost) by hades.hell.gr (8.12.5/8.12.5/Submit) id g7NH40g2062264; Fri, 23 Aug 2002 20:04:00 +0300 (EEST) (envelope-from keramida@ceid.upatras.gr) Date: Fri, 23 Aug 2002 20:03:59 +0300 From: Giorgos Keramidas To: Carlos Carnero Cc: wmoran@potentialtech.com, freebsd-questions@FreeBSD.org Subject: Re: optimization changed from TIME to SPACE ?! Message-ID: <20020823170359.GB50204@hades.hell.gr> References: <20020823162707.GA43840@hades.hell.gr> <20020823164815.38590.qmail@web21401.mail.yahoo.com> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Content-Disposition: inline In-Reply-To: <20020823164815.38590.qmail@web21401.mail.yahoo.com> X-PGP-Fingerprint: C1EB 0653 DB8B A557 3829 00F9 D60F 941A 3186 03B6 X-Phone: +30-944-116520 Sender: owner-freebsd-questions@FreeBSD.ORG Precedence: bulk List-ID: List-Archive: (Web Archive) List-Help: (List Instructions) List-Subscribe: List-Unsubscribe: X-Loop: FreeBSD.ORG On 2002-08-23 09:48 +0000, Carlos Carnero wrote: > > Your /var filesystem is almost 100% full. > > I thought so the moment I saw the message, but for > several months now I monitor that box using SNMP and > that partition is *always* kept very loose space-wise. That's funny, because space optimization kicks in only when the free space drops below a certain percentage in FreeBSD's filesystem. The default behavior is to allocate blocks & fragments from a filesystem in the fastest way possible, without taking a lot of care to avoid excess fragmentation of existing blocks. When the free space drops below a certain percentage, the filesystem code tries to avoid fragmenting disk blocks too much, and turns on "space optimization" instead of the default "time optimization". This uses slower algorithms for selecting the blocks & fragments of a file when it's written to, but saves some space. > Filesystem 1K-blocks Used Avail Capacity Mntd > /dev/ad0s1a 248047 38637 189567 17% / > /dev/ad0s1f 10163179 3081838 6268287 33% /usr > /dev/ad0s1e 26341315 9609257 14624753 40% /var > procfs 4 4 0 100% /proc Are you sure there aren't peaks in the space usage of this filesystem that you might miss while using df? -- FreeBSD: The Power to Serve <> http://www.FreeBSD.org FreeBSD 5.0-CURRENT #0: Wed Aug 21 22:08:19 EEST 2002 To Unsubscribe: send mail to majordomo@FreeBSD.org with "unsubscribe freebsd-questions" in the body of the message